How to create the curved effect on top of a sconce
When you see an object like this one, repeating a pattern all around a circle, you can use tools like Array modifiers, then SimpleDeform or Curve modifiers. Also it seems like there is a metallic structure, so I've tried something like that:


Create your basic shape, use a Mirror modifier to make it simpler. Enable the Clipping option.
Give it an Array modifier so that it repeats 5 times or more (?). Enable the Merge option.
Give it a SimpleDeform modifier / Bend mode. Choose a Deform Angle of 180°. If it doesn't turn around the Z axis as expected, you need to apply the rotation of the object with a ctrlA.
Give it a Subsurf modifier if you want, in that case, add some edge loops close to the angles.
You can add a glass surface on the same object, etc...